The present invention relates generally to support structures and more particularly to floating support structures or platforms. Various efforts have been made in the past to attenuate the motion of floating platforms caused by waves. Waves exert both horizontal and vertical forces on the platforms. Others have found that extension of the floats supporting the platform to depths below the water surface level attentuates the vertical forces exerted by the passing waves. The extension of the supporting members below the water surface, however, increases the moment arm and resulting horizontal forces applied to the platform through the supporting members.